Laser technique for determination of angular and energetic characteristics of high-current proton beam

A method for determination of angular and energy characteristics of a high-current proton beam based on laser effect in the Ar-N2 gas mixture is suggested. Angular characteristics are determined by laser beam visualization. For this purpose the proton beam is injected through a foil into Ar+N2 gas mixture. If the mixture is placed into the optical resonator the axis of which is transverse to the vector of proton velocity and quality factor of the resonator is rather high then lasing on UV transitions of N2 molecule arises. Threshold density of beam current is < or approximately 1 A/cm2, minimum cross dimension is 3-4 cm, energy is > 0.5 MeV. The method has angular resolution of approximately 1 deg and energy resolution not worse than 40% for 1 MeV protons. Calculated distributions of radiation intensity in a laser beam for σ-like and uniform spectra are presented. An experimental curve obtained by the described method and displaying qualitative agreement with the calculation is presented